Huge development as path cleared for Sweden and Finland's Nato membershippublished at 10:48 British Summer Time 29 June 2022
Frank Gardner
BBC security correspondent reporting from Madrid
After four months of dire news from Ukraine, Nato officials finally have something to celebrate this morning.
Ankara had objected to Nato applicants Finland and Sweden hosting Kurdish activists, whom it viewed as terrorists.
But overnight, in an early and significant boost to the Madrid summit, Turkey dropped its opposition to their impending membership of the alliance.
Facilitated by Nato Secretary-General Jens Stoltenberg, foreign ministers from all three countries came up with a formula that satisfied all parties, signing a memorandum of understanding which guarantees to protect each other's security.
For Nato, struggling to provide Ukraine with enough weapons to hold back the slowly advancing Russians, it's a huge development.
Finland and Sweden bring with them sophisticated armies, cutting-edge technology and lengthy Baltic coastlines.
But it's not all good news.
Today, Boris Johnson will warn fellow Nato delegates at the summit they will have to "dig deep" to prepare for a more dangerous decade ahead.
The British PM is expected to announce a number of commitments to Nato, including the expansion of the UK's base in Estonia.